100TQW MAC14 MC-2 won't start

[quk at isham-research.freeserve.co.uk]

Odd happenings.

While we were rebuilding the Bg Red Bus, I borrowed
Roger's 200TQ (1B engine, MAC12).  The autocheck unit
was occasionally signalling 'oil' and 'battery', although both
were fine. To get the Bus going again, I installed the 200TQ's
battery in it, and thought at first I had the same symptoms.
But the 'oil' warning was consistent at 3000rpm.

Nothing wrong with the oil - checked level and added a
mechanical pressure gauge.

Then I switched the battery back, and the REAL problems
started.  The car won't start (no spark) and the ECU
cnsistently stores 'coolant sensor'.  Also the tachometer
jumps to 3500 revs as soon as the key is turned.

Tride the spare ECU - no different.  Currently stripping and
cleaning the dashboard.

Any ideas?

--
 Phil Payne, UK Audi quattro Owners Club
 Phone: +44 7785 302803   Fax: +44 7785 309674